Question

Priya and Joe travel the same 16.8 km route. Priya starts at 9.00 am and walks at a constant speed of 6 km/h Joe starts at 9.30 am and runs at a constant speed. Joe overtakes Priya at 10.20 am At what time does Joe finish the route?

Answer 1

Answer:

12:05 PM

Step-by-step explanation:

Priya started at 9:00 AM.

Speed of Priya = 6 km/hr

Joe started at 9:30 AM.

Time at which Joe overtakes Priya = 10:20 AM

Total time taken by Priya = 1 hour 20 min = $\frac{4}{3}\ hr$

Total time taken by Joe = 50 min = $\frac{5}{6}\ hr$

Distance traveled by Priya and Joe is same.

Formula for distance is:

$Distance =Speed\times Time$

Distance covered by Priya = $6 \times \frac{4}{3}$ km

Let speed of Joe = $S$ km/h

Distance covered by Joe = $S \times \frac{5}{6}$

$S \times \dfrac{5}{6} = 6 \times \dfrac{4}{3}\\\Rightarrow S =\dfrac{48}{5}\ km/hr$

Total distance to be covered = 16.8 km

Total time to be taken by Joe =

$\dfrac{16.8}{\frac{48}5} = \dfrac{16.8\times 5}{48} = \dfrac{84}{48} = 1.75\ hours$

1.75 hours mean 1 hour and 45 minutes.

Finishing time at which Joe finishes = 9:30 AM + 1 hour 45 minutes = 12:05 PM